Firewise

Landscaping FOR UTAH

ACKNOWLEDGEMENTS AUTHORS: Michael Kuhns and Barbara Daniels

CONTRIBUTORS: East Bay Municipal Utility District, Oakland, California: graphics Utah Division of Forestry, Fire and State Lands, Lone Peak Conservation Center: photos Andrea Bell, Andrea Bell Graphic Design: graphic design and layout Justin Black, USU Extension Forestry: production assistance Darren McAvoy, USU Extension Forestry: photos and production assistance

REVIEWERS: Yvonne Barkley - University of Idaho Forestry Extension Frank C. Dennis - Colorado State Forest Service Kathy Hammons - Community Solutions Jeannette Hartog - USDA Forest Service Intermountain Region and USDI Bureau of Land Management Susan Lauman - Utah Divison of Forestry, Fire and State Lands Darren McAvoy - Utah State University Forestry Extension Teresa Prendusi - USDA Forest Service Intermountain Region Alix Rogstad - University of Arizona Cooperative Extension Joanne Skelly - University of Nevada Cooperative Extension

The authors wish to thank USDA Forest Service State and Private Forestry for assistance in producing this publication. Special thanks also to the Utah Living with Fire Committee for assistance and advice.

FIREWISE LANDSCAPING FOR UTAH

Firewise Landscaping for Utah

TABLE OF CONTENTS Fire and People in the Wildland - Urban Interface ……………1 How Do Wildfires Behave? …………………………………… 2 Property Selection and Construction …………………………4 Firewise Landscapes and the Home Ignition Zone……………6 Firewise Landscape Design ……………………………………8 Landscape Maintenance……………………………………… 12 Firewise Plant Selection ……………………………………… 14 Grasses …………………………………………………16 Ground Covers…………………………………………18 Herbaceous Perennials ……………………………… 20 Shrubs and Woody Vines………………………………24 Trees ……………………………………………………28 Other Fire Safety Factors ………………………………………30 The Last Word ………………………………………………… 32 References………………………………………………………33 For More Information …………………………………………34

FIREWISE LANDSCAPING FOR UTAH

“Your own property is concerned when your neighbor’s house is on fire.” Horace, Epistles

Wildland fires affect many communities in Utah and the Intermountain West each year. As this is being written the 2005 fire season is beginning strong in southern Utah and Arizona. This booklet is intended as a guide for homeowners and others concerned with management of the wildland-urban interface. Following the advice in this booklet will help you reduce the fire hazard around your home. There are no guarantees that a home will be fireproof, but if you take action to be firewise, you can greatly increase the chances that your home will withstand a wildfire.

FIREWISE LANDSCAPING FOR UTAH

FIRE AND PEOPLE IN THE WILDLAND-URBAN INTERFACE As Utah’s population grows, development

the information presented in this booklet,

merges the edges of cities and towns into

you can create a landscape on your prop-

wildlands. New developments also spring

erty that will be as firewise as possible. Land-

up within wildlands, including everything

scapes can never be fire-proof, but using

from a single cabin in the woods to hundreds

these recommendations will give you and

of vacation homes on slopes scattered

firefighters a higher chance of protecting

through the forest. These areas are called

your property.

the wildland-urban interface (WUI), where the places we live and play meet the wilds. These wildlands carry a substantial risk of burning in a wildfire due to accumulations of fuels such as dried grass, trees and brush. Dead and living vegetation is often continuous across wildlands, and as a result a fire can spread easily across the entire area. Also, many of the plant species in such areas are readily adapted to wildfire, so their means of reproduction, fire survival strategies, and growth habits all contribute to making fire a natural and common part of

New construction in the wildland-urban interface.

these landscapes. Cultivated landscapes within WUI areas, with mown grass, pruned trees, and carefully placed groups of appropriate vegetation, are less likely to burn. In these well-tended areas, continuous fuel corridors are disrupted, so fire is less likely to spread. Firewise Landscaping for Utah describes how to create and maintain landscapes around homes, cabins and other buildings to reduce fire risks. Principles and suggestions for building placement, plant choice and placement, and landscape maintenance are explained. An extensive list and photos of firewise trees, shrubs, herbaceous perennials, and grasses are included. By following

People are seeking out homesites with natural amenities. Along with ridgetop views and forested surroundings comes wildfire risk.

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FIREWISE LANDSCAPING FOR UTAH

HOW DO WILDFIRES BEHAVE? FUEL

Before you can properly establish and maintain your firewise landscape, you need to understand how fire works. Fire requires three things to exist: fuel, oxygen, and heat. Fire researchers and firefighters call this the “fire triangle.” Fuel is any combustible material, including dried grasses and dead branches, but also living plant material, a firewood pile, cleared brush that is not removed, a propane tank, and even your house or cabin. Oxygen HEAT

OXYGEN

must be present for a fire to start or continue, and there must be sufficient heat to allow for ignition and to sustain burning. If any one of these three is missing or is removed, the fire either cannot start or it will go out. Fire fighting, fire prevention, and firewise landscaping prevent or suppress fires by attacking one or more of the fire triangle legs: by removing fuel, reducing heat, or making oxygen unavailable. The initial source of ignition or heat for most wildfires is human activity, such as escaped debris fires, careless use of fireworks, overheated equipment, and arson. Lightning is the main natural ignition source. Once a fire has begun, there are several factors that affect how it behaves: WIND. Wind provides oxygen to a fire – the stronger the wind, the hotter the fire will burn and the faster it will spread. It also causes heat transfer from the fire to cooler areas, and partially determines the direction the fire will take. TOPOGRAPHY. Hot air rises, so fire will generally burn up a slope much more quickly

This fire began in the power lines at the bottom of the mountain and burned up the west-facing slope. Fortunately, no homes burned.

than down. Unburned fuels above the fire are preheated and dried, bringing them to the ignition point sooner.

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FIREWISE LANDSCAPING FOR UTAH

Fuel can be from nature, like pine needles, or man-made, like wood shakes. Fires don’t know the difference.

Continuous fuels and a wood roof increase this home’s risk for damage from a wildfire.

HUMIDITY. Humid air absorbs

Influenced by these factors, a wild-

initely affect fuel availability and

heat and makes fuel moister and

fire moves across the landscape by

distribution by manipulating the

harder to ignite. Humidity is low in

flame-heating near the fire or by

amount of fuel, continuity of fuel,

Utah in summer and early fall, when

airborne firebrands that spread the

and available moisture. Controlling

most wildfires occur.

fire far away from the flame front.

these factors is the key to creating

In extreme wildfires intense winds

a firewise landscape.

TEMPERATURE. High temperatures bring fuels closer to the ignition point. As with low humidity, high summer and fall temperatures create more fire-prone conditions. FUEL. A fire needs fuel to burn. Continuous fuels such as dead grasses, leaves, and branches will sustain a fire. Fire can also travel from the ground into the vegetation canopy, or up into a structure, if there are continuous fuels leading up into

can carry flaming brands or embers miles ahead of the main fire, causing landscapes and homes to ignite before the main fire even reaches them. This is the primary cause of homes burning in wildfires. Wind, temperature, and humidity are out of your control. The effect of topography can be controlled to some extent by how structures and plants are placed within the

The remainder of this booklet describes specific actions you can take to make your property as firewise as possible. They are divided into the following sections:

• Property Selection and Construction

• Firewise Landscape Design • Landscape Maintenance • Firewise Plant Selection • Other Fire Safety Factors

landscape. However, you can def-

the tree crown or building.

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FIREWISE LANDSCAPING FOR UTAH

PROPERTY SELECTION AND CONSTRUCTION You may already own a home or

system, pool, lake, stream, or an

LOT SIZE. A smaller lot restricts

a piece of property, but if you are

underground cistern can increase

your options for firewise landscap-

purchasing land or selecting a

the probability that structures can

ing, since you have less space to

building site, there are choices that

be protected.

work with. Small lots increase your

can reduce your wildfire risk. LOT LOCATION.

dependence on your neighbors for

Utah is can-

yon country, and canyons channel wind that can intensify and direct fires. Ridges are also fire-prone, since heat and wind quickly rise to ridgetops. Though the top of a steep ridge is scenic, when it comes to fire safety flatter land is a better location for a home or cabin. When evaluating property location, firefighter response time is another

VEHICLE ACCESS. When plan-

fire safety. If your firewise property

ning access to a new property, build

is surrounded by properties with

fire safety into the road design.

hazardous fuel conditions, your ef-

Multiple access roads are ideal.

forts may not be enough to prevent

Roads should be at least two lanes

fire damage to your property. With

wide, with gentle curves, and with

a small lot you will need to collabo-

enough space at the end for a fire-

rate with your neighbors to create

fighting vehicle to turn around. This

a firewise community.

can take at least a 45 foot radius circle, or a 60 foot wide ‘T’. Narrow, windy, steep, or vegetation-choked roads will be difficult or impossible for firefighters to navigate.

important consideration.

HOME POSITION.

Proper po-

sitioning of your home or other structures on your property is critical to fire risk and safety. Avoid

Make sure street signs and house

locating structures at the top of

Water

numbers are visible, reflective, and

a steep ridge or hilltop. A wind-

fire

readable in the dark. All address

propelled fire moving uphill will

suppression. Ability for firefighters

and street signs should be made of

quickly come in contact with the

to access water through a hydrant

non-combustible materials.

structure. Instead, the home should

WATER AVAILABILITY. access

is

important

for

Placement of this house on top of a Gambel oak-covered ridge puts it at greater risk from wildfire, along with its wood decks.

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FIREWISE LANDSCAPING FOR UTAH

be set back from the edge of the slope. If the home is already in place on a ridge, a concrete wall or patio, or even a pool between the home and the edge of the hill are

DANGEROUS MATERIALS AND CONDITIONS FOR SLOPED SITES

advisable additions. A wooden deck overhanging a hilltop or canyon also is vulner-

Wind 50 MPH

able to fire because fire will burn up the hill and under the exposed deck. Flammable decks and walkways should not be built near a house in a hazardous area. Structures that are open to fire from below should be enclosed with fire-proof materials, or even a concrete wall. ROOFING. Airborne burning embers or firebrands are the main source of wildfire

Wood shake roof Wood siding House built at edge of slope Deep overhang

spread. Therefore, roofing material is one of

Large trees with canopies touching

the most vital decisions in home or cabin construction. Choose Class A materials which have the top rating for fire resistance. Class A roofing includes tile and metal, plus shingles made of a variety of materials: fiberglass reinforced asphalt, metal, fibercement, concrete, or slate. Make certain the

LANDSCAPING AND STRUCTURES DESIGNED FOR FIRE SAFETY

underlayment material for any roof type is

Wind 50 MPH

also Class A. Be sure to properly enclose the edges of tile roofing. All roofing should be carefully maintained, so that openings for airborne embers are not created. These are key points to consider while constructing or renovating a home or cabin. In addition to the choices above, using fire-resistant materials for siding, eaves, decks, and fences will increase structure sustainability during a wildfire. Work closely with your contractor to make the best choices

Stucco siding Fire resistant roof; minimal overhang Concrete wall to deflect heat; house set back from top of slope Fuel reduced; some plants for stability Trees pruned and widely spaced

for fire preparation and prevention.

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FIREWISE LANDSCAPING FOR UTAH

FIREWISE LANDSCAPES AND THE HOME IGNITION ZONE The key to protecting yourself and your home in a fire-prone area is creating and maintaining a firewise landscape in the “home ignition zone” (Cohen 2002). The home ignition zone is the home and its immediate surroundings within about 100 to 150 feet. A house burns or survives depending on the characteristics of this zone, so this is where the homeowner needs to focus most of their pre-fire landscaping and home-care efforts. Firewise landscape design and maintenance in this zone interrupts the natural path a fire takes as it moves by flame heating and flying firebrands by decreasing fuel amounts and breaking up fuel continuity at and near the home. Additionally, firewise landscaping in this zone may allow firefighters to stay and safely defend the house, and can help prevent a house fire from spreading to adjacent vegetation. This home’s green, moist vegetation and setback from the hillside prevented it from igniting in the fire that burned up the hill. The wooden deck is a problem, and should be replaced with non-flammable material.

Firewise landscaping in the home ignition zone may be the make-or-break factor in the event of a wildfire. If firefighters can reach your home during such a fire, they will quickly decide if they have a chance of protecting your property. They will be more likely to protect a property that allows quick, uninhibited equipment access and is not thick with brushy, continuous fuels. If your home or cabin is so remote that firefighters might not reach it anyway, your firewise landscaping may keep the fire from entering the home ignition zone, or cause it to burn out if it does. How wide should this zone of firewise landscaping be? Research has shown that on flat ground a 100 foot wide space around a

06

NIFC Interagency Fire Prevention

FIREWISE LANDSCAPING FOR UTAH

Firewise landscaping in the home ignition zone, along with good access, protected this home from a wildfire.

home is ideal, since buildings ex-

uphill, heating the vegetation and

tion with your neighbors. If you

posed to heat from a fire more than

fuels above them. Very steep slopes

have a small lot, you won’t have 100

100 feet away are unlikely to ignite.

(greater than 40%, or 40 feet of rise

feet and may not have even 30 feet

This space includes a closer-in, more

per 100 feet horizontal distance)

around your home – part of your

manicured, green, and well-watered

may widen the home ignition zone,

home ignition zone may be on your

area about 30 feet out from the

and thus the width of your needed

neighbors’ properties. However, if

structure, and a low-fuel but less in-

firewise landscaping, out to as much

adjacent homeowners are aware

tensively managed area out to 100

as 200 feet.

and concerned with protecting

feet. Houses on steep slopes have

their homes, you can develop com-

wider home ignition zones, since

Developing wide enough firewise

flames move quickly and readily

landscaping may require coopera-

mon firewise landscapes.

FIRES ADVANCE BY DIRECT FLAME CONTACT AND BY AIRBORNE FIREBRANDS

Advancing flame front

Airborne firebrands Firebrands igniting landscape and house

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FIREWISE LANDSCAPING FOR UTAH

FIREWISE LANDSCAPE DESIGN In planning firewise landscaping, divide your property into several zones: Zone 1, the Near Zone, is immediately adjacent to the home or cabin and extends out 30 feet. It is generally very low in fuel and welltended. This zone is sometimes referred to as your defensible space. Zone 2, the Mid Zone, is 30 to 100 feet away This home has good, wide firewise landscaping within much of its home ignition zone. Its Zone 1 is “clean and green”.

from the house, and may be less manicured than the near zone, but usually is maintained as a low density fuel break. Zones 1 and 2 together constitute the home ignition zone, and thus the space requiring the most intensive firewise landscaping. Zone 3, the Far Zone, is a transition zone where the firewise landscape area meets the adjacent wildlands or open space. Note that these distances are for level properties with moderate vegetation densities. They need to be increased for steeper slopes and denser vegetation. Within each zone you have numerous opportunities to put firewise practices into place. These practices are detailed below.

Although this home close to the road, its Zone 1 landscaping is not firewise, with highly flammable oak trees overhanging the roof.

Zone 1: Within 30 feet of the building

• Plant widely-spaced, low-growing, non-resinous shrubs, 2-3 feet away from the house. Do not plant directly under windows, vents, or decks. Do not plant under tree crowns, or use shrubs to screen propane tanks or firewood piles.

• If planting new trees, plant small-maturing ones, at least 15 feet away from structures. 08

FIREWISE LANDSCAPING FOR UTAH

Choose “clean” trees that do not

• Maintain this zone well; it should

These areas create fire breaks be-

drop more leaves, bark, pods,

be clean and green. Remove ac-

tween regions of flammable ma-

etc. than you are willing to clear

cumulations of woody debris, dry

terials.

regularly. Leave plenty of room

herbaceous material, and needles.

between trees to allow for their

Mow lawns, prune shrubs and

growth. In this zone, there should

trees, and thin and prune ground

be at least 10 feet separating ma-

covers and other vegetation.

ture tree crowns to keep fire from moving across the landscape

• Remove

from tree to tree.

• Remove excess brush and small

cording to plant needs; use most of your available irrigation water in this area. Plants with sufficient moisture will be less flamma-

ground, within 15 feet of a chim-

ble. However, over-watering can

ney, or touching or overhanging

cause excess growth with some

the house. Limbs encroaching on

plants.

by the power company.

and can provide a “fire ladder”

Zone 1 well watered ac-

tree limbs near the

power lines should be removed

trees. Dense brush burns quickly

• Keep

• Remove firewood and other combustible materials from around

for low flames to move into taller

• Include non-flammable mulches,

buildings. Firewood should be

trees. Widely spaced trees and

rock, and hard surfaces (concrete

stored on the outside edge of

shrubs can be left in the land-

walks, brick patios, asphalt drive-

your home ignition zone or as far

scape for shade and esthetics.

ways), especially near the house.

out as possible.

HOME IGNITION ZONE AND FUELS TREATMENT ZONES NEAR AN INTERFACE HOME HOME IGNITION ZONE ZONE ONE (NEAR AREA)

ZONE TWO (MID AREA)

ZONE THREE (FAR AREA)

Defensible space

Reduce fuel load in transition zone

Prune and thin trees and shrubs

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FIREWISE LANDSCAPING FOR UTAH

Zone 2: 30-100 feet away from the building

• Maintain

a fuel break of low-

growing plants in this zone. Such fuel breaks act as a buffer between the manicured landscape near the home and adjacent wildlands.

• Emphasize

low-growing plants,

up to 18 inches high, such as fire

• Do

not plant in large masses.

prone areas it can be hazardous.

Instead, plant in small, irregu-

Thinning these groups will slow

lar clusters or islands. Separate

the spread of fire.

shrubs by at least 2 times their mature height.

litter.

• As in Zone 1, routinely remove any excess brush or dead vegetation.

be spaced 20 to 30 feet between crowns to prevent lateral fire spread. Prune all lower branches within 8 feet of the ground without leaving stubs.

If some of these zones are outside of your property line, cooperate

Zone 3: Beyond 100 feet; transition to wildlands

with neighboring landowners to

• Prune and thin trees and brush in

wish to notify larger landowners

resistant ground covers.

• Any trees within this zone should

• Prevent buildup of dry brush and

this zone. Break up the “fire ladder” leading from brush up into trees.

create a firewise condition. You may such as the Forest Service, Bureau of Land Management, the state, or others of the existence of your home or cabin adjacent to

• Thin dense tree groups. Though

their property. Be sure to learn

tree grouping is normally a good

about their fire prevention and

landscaping technique, in fire-

suppression plans.

These homeowners are raking and removing pine needles and other debris, and pruning dead material from shrubs. In general, this home has a good Zone 2, with low and widely-spaced plants. However, the large spruce and pine represent a lot of fuel that nearly allowed a wildfire to reach the house.

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FIREWISE LANDSCAPING FOR UTAH

VEGETATION CLEARANCE AND ROOF COMPOSITION ARE KEYS TO IGNITION PREVENTION

Darren McAvoy

In 1997, Forest Service fire scientist Jack Cohen carried out a revealing experiment (Cohen, 2000). As part of a research project on crown fires, he tested the ignitability of wood home walls at varying distances from crown fires. He found that a wall 33 feet away from an intense crown fire (with flame

This home did not have sufficient clearance from the surrounding forest because of a nonfirewise landscape within their home ignition zone.

lengths sometimes reaching 33 feet) only ignited if flames actually touched the wall. A wall placed at 66 feet from the forest was lightly scorched, and a wall placed at 99 feet was not scorched. The lesson here is that even if your property is surrounded by forest, proper clearance around your home, along with Darren McAvoy

good maintenance, can protect it from ignition. Roof composition is another key factor. One study showed that homes with nonflammable roofs and a vegetation clearance of 33 to 60 feet had a 95 percent fire survival rate (Howard et al. 1973). A study of a 1990 fire in Santa Barbara reported that homes

This home survived a very hot crown fire passing nearby. Good firewise landscaping, especially in Zone 1, along with a non-flammable roof and other firewise features contributed to the home’s safety, even with a large pine tree very near.

with nonflammable roofs and a vegetation clearance of at least 33 feet had an 86 percent fire survival rate (Foote 1994).

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FIREWISE LANDSCAPING FOR UTAH

LANDSCAPE MAINTENANCE Maintenance of your firewise land-

frequent, shallow watering. Water

stay green and healthy, while oth-

scape is just as important as plan-

wide areas around trees and shrubs,

ers, like bluegrass, need more.

ning and installation. Any planted

since their roots extend well away

landscape, even one planned with

from their trunks or stems.

fire safety in mind, can become over-

• When

• Rake up and remove dead pine needles, leaf litter, and other plant

possible, install drip irri-

debris. Don’t pile these materials

lar, mindful maintenance. Here are

gation in planting areas. This

in Zones 2 or 3; get rid of them

suggestions for keeping your fire-

will conserve water while giving

completely. Neighbors may want

wise landscape in shape:

plants optimum moisture.

to cooperate to arrange chipping

grown and hazardous without regu-

and removal if large amounts of

• Water your landscape as necessary • Mow and water grass regularly,

material are involved. If possible

succulent

according to its needs. Tall, dry

take material to a composting/

vegetation. Do not allow plants

grasses can spread a fire to your

recycling facility where it can be

to dry out, thus increasing fire

home or other combustible ma-

processed for use elsewhere. If you

risk. Less frequent, deep watering

terials. Some grasses, like buffa-

maintain a compost pile in your

is better for most plants than

lograss, need fairly little water to

to

maintain

green,

POORLY MAINTAINED LANDSCAPE

Tree overhanging roof and chimney

Tree branches growing down to shrubs Masses of shrubs against house

Continuous masses of shrubs

WELL MAINTAINED LANDSCAPE Tree thinned and pruned up Shrubs next to house removed

Adequate space between shrubs and tree Shrubs in distinct groups Low groundcover or mulch

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FIREWISE LANDSCAPING FOR UTAH

yard, try to place it at least 100 feet away from your house.

• Remove

tops of annual and

perennial plants after they have gone to seed or when the stems become dry.

• Keep

shrubs small by pruning

them off close to the ground annually, or at least remove dead wood and prune branches regu-

Rake and remove dead leaves, needles and other debris from wood structures.

larly. Do not allow shrubs to grow against the side of structures, or up into tree crowns.

• On large trees, prune branches to a height of 10 to 20 feet above the ground to help prevent low fires from reaching the tree crowns.

Glenn Beagle

Maintenance is a never-ending task. Inspect landscapes monthly and attend to problem situations before they become serious hazards. A brush disposal crew clears and chips thick underbrush.

MAINTENANCE IS KEY Even with good firewise landscape design, fire can still burn unmaintained structures if debris accumulates in the home ignition zone. Cohen (1999) cites several examples of homes that caught fire even though the wildfire was miles away. In one fire he found that removal of pine needles from the base of woodcovered walls kept several homes from igniting (Cohen 2000). Keeping your roof, foundation, decks, and the ground near your house clear of flammable debris is a critical activity all of the time, and especially as fire season approaches.

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FIREWISE LANDSCAPING FOR UTAH

FIREWISE PLANT SELECTION Firewise plants have a number of but

or no irrigation to remain green

also can vary considerably. Below

and healthy; over-irrigation may

are some important points about

harm such plants or may cause

these plants and their management.

them to grow too fast and become

Following this section is a list of

hazardous. Other plants will need

firewise

Utah

supplemental water to survive.

landscapes. This is only a partial

Know your plants’ needs and habits

listing. Many other plants could be

so you can use and manage them

considered firewise if they have the

appropriately.

characteristics

Evening Primrose

plant

in

common,

choices

for

appropriate characteristics.

• No plant is fireproof. All will burn in a very intense fire.

• When

choosing a particular plant

species or cultivar for a firewise planting, favor those that stay low

• Firewise plants all have one or more

to the ground, are compact, green

of these firewise characteristics:

and healthy with low maintenance

◊ Tissues contain more moisture,

and minimal water, especially dur-

especially during the fire season.

◊ Tissues contain low amounts of Lilac

• Some firewise plants need minimal

ing the dry season.

• All

firewise plants should receive

volatile oils and other readily

periodic maintenance, including

flammable chemicals.

removal of dead leaf and stem ma-

◊ Plants provide less fuel, either by

terial within the crown and on the

producing less litter or by staying

ground, pruning to keep crowns

small.

clean and high, and removal of in-

◊ Plants are compact or low to the ground, so they can be used in the landscape to interrupt fire pathways.

dividual plants to break up fuel continuity.

• Make sure that the plants you are considering are cold-hardy (check

• All trees provide large amounts of

the USDA hardiness zone for the

fuel to a fire, so they should be care-

plant and compare it to the zone for

fully placed and maintained. Broad-

your area) and otherwise well-suited

leaved trees found in Utah general-

for your locale and the specific

ly are less flammable than conifers

planting site.

(pines, firs, spruces, junipers).

• Most

of the firewise plants listed

• Some

plants are weedy and may

even be illegal to plant or cultivate.

in this publication do well in open, sunny areas typical of most fireprone sites. All plant photos by Michael Kuhns unless otherwise attributed.

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FIREWISE LANDSCAPING FOR UTAH

USING NATIVE PLANTS Using firewise plants native to your landscape often is the best option. Native plants may survive better, rarely are weedy, and may do well with little or no additional water or other resources. The important point is to know plants and your site well enough to choose plants appropriate to your site. Remember, just because a plant is native to your state doesn’t mean it is well adapted or native to your local area. Wasatch Penstemon – an herbaceous perennial native to the Wasatch mountains and foothills.

Aspen, for example, is native to the mountains throughout Utah, but not to warmer, drier valleys. So while aspen is a Utah native, it is not a good landscape choice away from the mountains.

Silvery Lupine – an herbaceous perennial native to higher elevations throughout Utah.

Creeping Oregon Grape – a low-growing shrub native to high elevation forests throughout Utah.

PLANTS TO AVOID Some plants are pyrophytic – these plants are extremely flammable due to high resin or oil content. Common pyrophytes in Utah landscapes are juniper, pine, fir, and spruce. Do not plant any of these species in your firewise landscape, or use them sparingly, and if they are already present, consider replacing them with some of the firewise species listed here. If you decide to keep a pyrophytic plant in your landscape, make sure it is pruned and thinned, remove dead material regularly, and keep at least 15 feet of clear space between this plant and any structure or other plant. 15

FIREWISE LANDSCAPING FOR UTAH

GRASSES Low-growing grasses are useful anywhere in a firewise landscape. They especially serve well as the primary landscape plants in Zone 2. Keep grasses well watered, and mowed or trimmed. In especially dry areas, consider using buffalograss or other grasses that require less water and are slow growing. Also look for grasses that are less prone to drying out during the summer.

Paul Johnson

RECOMMENDED FIREWISE GRASSES Common Name Scientific Name

Buffalograss

Kentucky Bluegrass

16

Wheatgrass

Agropyron species (some Native)

Buffalograss

Buchloe dactyloides

Orchardgrass

Dactylis glomerata

Blue Fescue

Festuca cinerea and other species

Rye Grass

Lolium species

Western Wheatgrass

Pascopyrum smithii (Native)

Kentucky Bluegrass

Poa pratensis

Sandberg Bluegrass

Poa secunda (Native)

Blue Fescue

FIREWISE LANDSCAPING FOR UTAH

Comments Eileen Coite, NCSU Cooperative Extension

resists fire spread due to growth form low growing without mowing; green through summer with minimal irrigation must be mowed or grazed most low growing; may need to mow; stays moist with irrigation stays green with less irrigation than some; need to mow or graze low fuel loads; regrows quickly after fire low growing; may need to mow; stays moist with irrigation

Orchardgrass

Tall Fescue

Blair Waldron

Morgan Mendenhall

low growing without mowing; low fuel loads

Crested Wheatgrass

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FIREWISE LANDSCAPING FOR UTAH

GROUND COVERS Plant low-growing ground covers in Zone 1 and/or in Zone 2, the midzone of your property. Ground covers often are succulent or have other firewise characteristics that make them useful, functional, and attractive. When planted in beds surrounded by walkways and paths, in raised beds, or as part of a rock garden, they are an effective barrier to fire spread. The best ground cover is a spreading plant which forms a dense mat of roots and foliage that reduces soil erosion while excludBearberry

ing weeds. Maintain ground covers by providing adequate irrigation, and clipping off and removing dead stems and other litter annually.

RECOMMENDED FIREWISE GROUND COVERS Common Name Scientific Name Bearberry, Kinnikinnick, Manzanita

Arctostaphylos uva-ursi (Native)

Sea Pink, Sea Thrift

Armeria maritima

Beach Wormwood, Dusty Miller

Artemisia stelleriana

Snow-in-summer

Cerastium tomentosum

Bearberry Cotoneaster

Cotoneaster dammeri

Hardy Ice Plant *

Delosperma nubigenum (yellow) & other Delosperma species

Evergreen Candytuft

Iberis sempervirens

Spring Cinquefoil, Creeping Potentilla

Potentilla neumanniana ‘Nana’ (P. verna)

Stonecrop, Sedum

Sedum species (some Native)

Hen and Chicks

Sempervivum tectorum

Periwinkle *

Vinca species

Sea Pink

*Can become weedy in certain circumstances.

Evergreen Candytuft

18

Snow-in-summer

FIREWISE LANDSCAPING FOR UTAH

Hardy Ice Plants

Comments very low and spreading; evergreen; use on poor soils; needs little pruning; salt tolerant low growing; dry, infertile sites only; salt tolerant needs very well-drained soil; moist in summer low growing; fairly moist in summer low growing; evergreen; minimal maintenance; dry sites also other ice plants; succulent; very drought tolerant; low growing; may be weedy in warm climates fairly low growing; evergreen

White Stonecrop

very low growing very low growing; fleshy, moist leaves; drought tolerant very low growing; succulent; good on dry, poor soils low growing, prostrate ground covers; sun or shade; vincas can spread aggressively

Hen and Chicks

Large Periwinkle

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FIREWISE LANDSCAPING FOR UTAH

HERBACEOUS PERENNIALS Herbaceous perennials in your landscape will add color and variety. However, tall perennials can present some fire danger if allowed to dry out. To reduce fire hazard, plant herbaceous perennials in widely spaced beds in Zones 1 and 2. As with ground covers, separate beds with gravel walkways, rock walls or areas of mown lawn. Do not plant these perennials next to structures unless they are small in stature, frequently watered and weeded, and tops removed after the first hard frost. Keep all perennial beds watered, and prune away dead stalks and foliage throughout the summer and fall. Columbine

Dianthus

RECOMMENDED FIREWISE HERBACEOUS PERENNIALS Common Name

Scientific Name

Silvery Yarrow

Achillea clavennae

Fernleaf Yarrow

Achillea filipendulina

Yarrow*

Achillea — other species & hybrids (some Native)

Columbine

Aquilegia species & hybrids (some Native)

Artemisia (various names)*

Artemisia — species & hybrids (some Native)

Bergenia

Bergenia species & hybrids

Red Valerian, Jupiter’s Beard

Centranthus ruber

Dwarf Mouse Ear Coreopsis

Coreopsis auriculata var. Nana

Coreopsis

Coreopsis — perennial species

Pinks

Dianthus plumarius & others

Fleabane*

Erigeron species & hybrids (some Native)

Blanketflower

Gaillardia x grandiflora hybrid & other species (some Native)

Hardy Geranium

Geranium cinereum

*Can become weedy in certain circumstances.

Artemisia ‘Silver Mound’

20

Red Valerian

FIREWISE LANDSCAPING FOR UTAH

Coreopsis

Comments small plants for dry sites

Blanketflower

large; likes dry sites; moist in summer some are volatile; good for dry sites likes moisture and some shade some are volatile; all like dry soils moisture loving; medium-sized; semi-evergreen gets fairly large; moist in summer needs moisture; fairly low growing more drought tolerant; larger plants use perennials; needs moisture; moist in summer moist through summer Fleabane

drought, heat tolerant; moist in summer; large; spreads from seed low growing; cool sites

Daylily

Hardy Geranium

21

FIREWISE LANDSCAPING FOR UTAH

FIREWISE HERBACEOUS PERENNIALS Common Name Scientific Name

Red-hot Poker

Bloody Cranesbill

Geranium sanguineum

Geranium

Geranium species (some Native)

Daylily

Hemerocallis species

Coral Bells, Alum Root

Heuchera sanguinea & other species (some Native)

Iris

Iris species & hybrids (some Native)

Red-hot Poker

Kniphofia species & hybrids

Lavender

Lavandula species

Shasta Daisy

Leucanthemum x superbum

Sea-lavender, Statice

Limonium latifolium

Flax

Linum species (some Native)

Lily-turf

Liriope spicatum

Lupine*

Lupinus species & hybrids (some Native)

Alfalfa

Medicago sativa

Primrose

Oenothera species (some Native)

Poppy

Papaver species (some Native)

Penstemon

Penstemon species & hybrids (some Native)

Russian Sage, Azure Sage

Perovskia atriplicifolia

Nepal Cinquefoil

Potentilla nepalensis

Cinquefoil, Potentilla*

Potentilla—other non-shrubby species & hybrids (some Native)

Salvia, Sage*

Salvia species & hybrids (some Native)

Wineleaf Cinquefoil

Sibbaldiopsis (Potentilla) tridentata

Lamb’s Ear

Stachys byzantina

Yucca

Yucca filamentosa & other species (some Native)

Lupine

*Can become weedy in certain circumstances.

Lavender

22

Penstemon

FIREWISE LANDSCAPING FOR UTAH

Comments low/medium growing; partial shade or sun use perennials; most low growing; need shade where hot green and moist through summer also other species, hybrids; low growing foliage green and moist through summer large plants; green in summer compact; contains oils but slow to ignite when moist; moist in summer; cut to ground regularly green and moist through summer low growing leaves; salt resistant; dry soils good for tough sites & soils Lamb’s Ear

fairly low growing; moist or dry sites; evergreen some are annuals; poisonous to livestock; good for poor soils green & moist through summer; low growing fairly low growing; best on poor soils easy to grow; cut back regularly use on well-drained soils green through summer; cut back yearly prostrate form sulfur cinquefoil is weedy; full sun; moist through summer

Heuchera ‘Coral Bells’

Heuchera ‘Purple Palace’

some are annuals; Mediterranean sage is weedy; only use low growing, small plants prostrate, spreading form green through summer; good on poor soils evergreen; very drought tolerant

Russian Sage

Yucca

23

FIREWISE LANDSCAPING FOR UTAH

SHRUBS AND WOODY VINES Shrubs add color and structure to a well-designed landscape. However, shrubs are a special concern in a firewise landscape, because they can be a source of significant fuel. Additionally, if shrubs are planted under tree crowns, under overhanging decks or adjacent to buildings, they can function as a fire ladder to spread flames to new areas. When planning your firewise landscape, plant shrubs individually, or plant in small clumps apart from each other. Near trees and buildings, plant only widely separated, low-growing, non-resinous English Ivy

varieties. Mow grass low around shrubs, and trim away dead leaves and branches annually.

RECOMMENDED FIREWISE SHRUBS AND WOODY VINES Common Name Scientific Name Saltbush

Atriplex species (Native)

Serviceberry

Amelanchier species (some Native)

New Jersey Tea

Ceanothus americanus

Ceanothus

Ceanothus ovatus (C. herbaceous) & others (some Native)

Mountain-mahogany Cercocarpus species (Native) Rock-rose

Cistus species

Rockspray, Rock Cotoneaster

Cotoneaster horizontalis

Cotoneaster

Cotoneaster—other compact species

English Ivy *

Hedera helix

Prostrate Kochia

Kochia prostrata

*Can become weedy in certain circumstances

Rockspray

24

Creeping Oregon Grape

FIREWISE LANDSCAPING FOR UTAH

Utah Serviceberry

Comments very drought tolerant; low maintenance fairly tough, attractive shrubs/small trees; nice flowers low, dense form; evergreen; fairly trouble free; drought tolerant fairly low growing; evergreen; low maintenance tough shrubs/small trees; curlleaf (C. ledifolius) species is evergreen and can get pretty large not all are cold hardy; evergreen; dry sites; size varies very low and spreading; evergreen low growth form; low maintenance; tough evergreen vine; low growing, spreading, climbing; prune to control spread; sun or shade; can be weedy stays green; no volatiles; clumps break up fuel continuity; don’t use weedy annual kochia (K. scoparia)

Spreading Cotoneaster

Honeysuckle

25

FIREWISE LANDSCAPING FOR UTAH

FIREWISE SHRUBS AND WOODY VINES

Buckthorn

Common Name

Scientific Name

Honeysuckle

Lonicera species & hybrids (some Native)

Creeping Oregon Grape

Mahonia repens (Native)

Western Sandcherry

Prunus besseyi (P. pumila var. besseyi) (Native)

Bitterbrush, Antelope Bitterbrush

Purshia tridentata (Native)

Firethorn, Pyracantha

Pyracantha coccinea

Buckthorn

Rhamnus species (some Native)

Skunkbush Sumac

Rhus trilobata (R. aromatica) (Native)

Sumac

Rhus—other species (some Native)

Currant, Gooseberry

Ribes species (Native)

Rugosa Rose *

Rosa rugosa & other hedge roses

Woods Rose

Rosa woodsii (Native)

Buffaloberry

Shepherdia species (Native)

Snowberry

Symphoricarpos species

Lilac

Syringa vulgaris

*Can become weedy in certain circumstances.

Skunkbush Sumac

26

Roundleaf Buffaloberry

FIREWISE LANDSCAPING FOR UTAH

Comments shrubs or vines; use low growing species, cultivars very low growing, spreading shrub; evergreen; needs some shade small, spreading shrub for dry, tough sites low maintenance; good for tough, dry sites evergreen shrub; use low growing selections; prune regularly tough shrubs; low maintenance

Firethorn

easy to grow shrub; fairly small; low maintenance fairly tough and drought tolerant; some get large; thin or prune periodically use low growing dwarf forms; fairly tough, adaptable medium shrub; tough, fairly drought and salt tolerant tough; drought tolerant; pink flowers does well on very poor soils; drought tolerant; fixes nitrogen; salt tolerant small shrubs; fairly tough small to large shrubs; stay green through summer with irrigation; thin and prune regularly Golden Currant

Woods Rose

Hedge Rose

27

FIREWISE LANDSCAPING FOR UTAH

TREES Any tree provides a large potential source of fuel for a wildfire, so include trees in your firewise landscape sparingly. In Zone1, trees should be small and placed at least 15 feet away from structures. In all zones, leave plenty of room between trees to allow for growth; keep 10 feet between mature tree crowns. Prune tree limbs up to a height of 10 feet above the ground, and do not allow shrubs to grow up under the trees, creating ladder fuels. Broadleaved (deciduous) trees are better firewise choices than conifers. Deciduous trees have higher moisture content, less flammable content, and provide less fuel during their dormant period. Most conifers have flammable resins, and their dry needles can drop and accumulate on roofs and the ground, giving fire a place to start and a way to spread. A few firewise trees are listed below, but there are many others. Just Bigtooth Maple

remember, any tree adds up to a lot of fuel, so trees should be used carefully in a firewise landscape.

RECOMMENDED FIREWISE TREES Common Name Scientific Name and Origin

Quaking Aspen

28

Maple

Acer species (some Native)

Thinleaf Alder

Alnus tenuifolia (Native)

Birch

Betula species (some Native)

California Redbud

Cercis occidentalis (Native)

Quaking Aspen

Populus tremuloides (Native)

Poplar, Cottonwood

Populus—other species (some Native)

Willow

Salix species (some Native)

FIREWISE LANDSCAPING FOR UTAH

Water Birch

Fremont Cottonwood

Comments needs supplemental moisture stays moist in summer but will need irrigation needs supplemental moisture; use borer resistant selections small tree or shrub; drought and heat resistant needs supplemental moisture; good if maintained in young clumps, otherwise not suitable for valleys needs supplemental moisture; most need plenty of space; some reproduce from sucker sprouts needs supplemental moisture; disease prone; some good shrubs

California Redbud

29

FIREWISE LANDSCAPING FOR UTAH

OTHER FIRE SAFETY FACTORS Creating and maintaining a firewise landscape in your home ignition zone will certainly reduce your risk of damage from a wildfire, but there are other steps you can take to lower the risk even further. As you prepare your property for fire safety, also consider the measures listed below.

BUILDING This home has a triple threat: wood shake roof, pine trees overhanging the house, and dead needles and other debris collected on the roof.

• Class A roof – As emphasized earlier, roof composition is one of the keys to your home’s ignitability. Use Class A materials for your roof if you are building. If your existing structure does not have a Class A roof, consider replacing it.

• Decks – Enclose, especially those that overhang a slope, with materials that will prevent sparks and firebrands from getting under them. Consider building or replacing wood decks and walkways with non-flammable materials. Never store combustible materials under your deck.

• Non-combustible soffits – If your home or building has overhanging eaves, enclose the underside (soffit) with non-combusThis woodpile should be moved at least 100 feet away from the house. Notice the unenclosed deck and tree growing up through the deck – both increase risk from a wildfire.

tible material. Cover soffit vents with metal screening to exclude embers.

• Screen on chimney – Make sure all chimneys have a spark arrestor or screening of onehalf inch mesh.

• Window

materials – Windows broken by

heat will let fire into a structure. Doubleor triple-glazed windows will last longer than single-pane windows during a fire. Tempered, low-E glass will last the longest. Smaller windows are less likely to break during a fire than are larger windows. 30

FIREWISE LANDSCAPING FOR UTAH

The road in this rural subdivision is clearly marked with a reflective sign.

• Skylights

- A skylight can melt

your home ignition zone (at least

other emergency numbers where

in the intense heat of a fire, cre-

100 feet away from the house).

they can be found quickly in the

ating an opening into the home.

Consider burying large propane

event of a fire.

You can easily construct covers for

tanks.

skylights out of 2x4s and shingles; then just put them in place if you are evacuated in the event of a wildfire.

MAINTENANCE

• Debris cleanup – Prevent buildup of pine needles and other debris.

EMERGENCY PREPAREDNESS

• Fire plan – Create a family fire

• Street signs and house numbers – Ensure that your street is marked with easily readable, visible, and non-combustible

signs.

House

numbers should be large, reflec-

plan. Know how you will contact

tive, and not obscured by vegeta-

each other, and where you will

tion. Post your house number at

meet in the event of a fire. Prac-

the end of the driveway if your

tice home fire drills.

house is not easily visible from the road.

Keep roofs, gutters, decks and porches free of dead pine nee-

• Hand tools – During fire season,

dles and other fine debris. They

keep hoses and hand tools (rake,

are highly combustible, and can

axe, hoe, shovel) easily accessible.

home is on well water with an

easily ignite and spread a fire.

Raking dead vegetation away

electrical pump, consider having

from your home and wetting your

an emergency generator, in case

roof as a fire approaches may pre-

the electricity fails during a fire.

vent your home from igniting.

A pool or pond can be a good

• Firewood, propane – Store firewood and propane away from

• Water

and electricity – If your

emergency water source for you

house. Woodpiles and propane tanks, including small gas grill

• Phone numbers – Post the fire

tanks, should be at the edge of

department phone number and

and firefighters.

31

FIREWISE LANDSCAPING FOR UTAH

THE LAST WORD—LET’S GET REAL

A firewise landscape set in Utah’s

Firewise landscaping can be at-

If you have a home or cabin in the

pine forests, juniper woodlands, or

tractive, but appreciating it may

woods and just cannot bear to dra-

oak hills may not look “natural” to

take an adjustment from what we

matically change your surround-

our eyes. Open space and thinned,

are accustomed to. Consider the

ing landscape to make it firewise,

spread out vegetation may not

example of water-wise landscaping.

take at least a few steps to reduce

appear as green and inviting as a

A decade ago, when few people

your risk of fire damage. Refer to

dense stand of trees. Many of us

were concerned with water conser-

the other sections of this booklet

would love to live in a home or cab-

vation, extensive green lawns sur-

for specifics, but here is the mini-

in nestled in the woods. However,

rounded by thirsty annuals were

mum you should consider:

when we make the choice to build

considered

in a wildland landscape, the homes

and “normal”. Now, low-water-use

we build are at the same risk from

landscapes filled with native and

fire as the surrounding vegetation.

water-wise perennials are becom-

pane tanks at least 100 feet away

Living in the woods comes at a price

ing more common and perceptions

from the home, preferably to an

– if it is not paid by landscaping to

of what is attractive are changing.

open area.

prevent fire, it might be paid by the

If we continue to build in wildland

loss of a home.

areas, our perception of what con-

beautiful, desirable,

•

tile, or non-flammable shingles.

•

•

Move firewood piles and pro-

Do not let dead pine needles and other flammable debris ac-

stitutes attractive surroundings in

cumulate on roofs and decks

those settings may need to change too.

Replace wood roofing with metal,

and around foundations.

•

Thin dead material from shrubs and trees. Remove any limbs that touch the side or roof of the home.

Your property will not be completely safe, but following these steps will help greatly.

32

FIREWISE LANDSCAPING FOR UTAH

REFERENCES Cohen, Jack D. 1999. Reducing the wildland fire threat

Foote, E.I.D. 1994. Structure survival on the 1990 Santa

to homes: Where and how much? USDA Forest Service

Barbara “Paint” fire: A retrospective study of urban-

General Technical Report PSW-GTR-173. At: www.fire-

wildland interface fire hazard mitigation factors. MS

lab.org/fbp/fbppubs/fbppdf/cohen/reducingwlfire.pdf.

thesis, University of California at Berkeley.

Cohen, Jack D. 2000. Examination of the home destruc-

Hagen, Bruce. 2003. Fire safe landscaping. Western Ar-

tion in Los Alamos associated with the Cerro Grande

borist 29(4).

fire. At: www.firelab.org/fbp/fbppubs/fbppdf/cohen/ losalamos.pdf.

Howard, R.A., D.W. North, F.L. Offensend, and C.N. Smart. 1973. Decision analysis of fire protection strategy for

Cohen, Jack D. 2000. Preventing disaster: Home ignit-

the Santa Monica mountains: An initial assessment.

ability in the wildland-urban interface. Journal of For-

Menlo Park, CA: Stanford University.

estry 98(3):15-21. Kuhns, Mike. 1998. Firewise plants for Utah landscapes. Cohen, Jack D. 2002. Wildland-Urban Fire—A different

Utah Forest Facts, NR/FF/002. Utah State University

approach. USDA Forest Service, Missoula Fire Sciences

Forestry Extension, Logan, Utah.

Laboratory, Rocky Mountain Research Station. Missoula, Montana. At: http://www.firelab.org/fbp/fbppubs/

Slack, Peter. Firewise construction: Design and materi-

fbppdf/cohen/wufire.pdf.

als. Colorado State Forest Service.

Cohen, Jack D. 2003. Protecting your home from

Southwest Fire Management Board. 2002. Living with

wildfire (video). USDA Forest Service, Missoula Fire

fire: A guide for the homeowner.

Sciences Laboratory, Rocky Mountain Research Station. Missoula, Montana. At: www.fs.fed.us/rm/main/videos/ protecting.html. Dennis, F.C. 1999. Fire-resistant landscaping. Natural Resources Series, no. 6.303. Colorado State University Cooperative Extension, Fort Collins, Colorado. Dennis, F.C. 1999. FireWise plant materials. Natural Resources Series, no. 6.305. Colorado State University Cooperative Extension, Fort Collins, Colorado. East Bay Municipal Utility District. 1992 and 2003. Firescape: Landscaping to reduce fire hazard. Oakland, California.

33

FIREWISE LANDSCAPING FOR UTAH

SOURCES FOR INFORMATION AND ASSISTANCE IN MAKING YOUR HOME/PROPERTY FIREWISE

• Contact your local fire department. • USU Forestry Extension: extension.usu.edu/forestry, or write to 5230 Old Main Hill, Utah State University, Logan, Utah 84322-5230. Forestry information and assistance for homeowners and forest landowners.

• Firewise: www.firewise.org. National organization providing information on how to make your home and property firewise. Includes a virtual tour of a firewise property.

• Utah Fire Info: www.utahfireinfo.gov. Information on fire prevention at home, on the job, and during recreational activities.

• Utah Division of Forestry, Fire and State Lands: www.ffsl.utah.gov/mmfiremgt.htm. Fire information from the state forestry agency in Utah.

• Hire an ISA (International Society of Arboriculture) certified arborist for tree work. A searchable list of certified arborists is found at www.isa-arbor.com/findArborist/ findarborist.aspx.

• USDA Forest Service: Contact your local Ranger District, or go to www.fs.fed.us to find the Forest and District nearest you.

• USDA Forest Service Rocky Mountain Research Station Fire Sciences Lab: www.firelab.org. Information on wildfire research and links to current wildfire activity.

• USDA Forest Service Center for Urban Forest Research: www.ecosmart.org. Click on the “fire” icon to link to ecoSmart-Fire, an interactive landscape planning tool that helps you make firewise choices for your home and landscape.

Utah State University is committed to providing an environment free from harassment and other forms of illegal discrimination based on race, color, religion, sex, national origin, age (40 and older), disability, and veteran’s status. Utah State University’s policy also prohibits discrimination on the basis of sexual orientation in employment and academic related practices and decisions. Utah State University employees and students cannot, because of race, color, religion, sex, national origin, age, disability, or veteran’s status, refuse to hire; discharge; promote; demote; terminate; discriminate in compensation; or discriminate regarding terms, privileges, or conditions of employment, against any person otherwise qualified. Employees and students also cannot discriminate in the classroom, residence halls, or in on/ off campus, USU-sponsored events and activities. This publication is issued in furtherance of Cooperative Extension Work, Acts of May 8 and June 30, 1914, in cooperation with the U. S. Department of Agriculture, Jack M. Payne, Vice President and Director, Cooperative Extension Service, Utah State University. Published July 2005.

34

NOTES

extension.usu.edu